#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<assert.h>

char* My_strcat(char* dest, const char* src)
{
	assert(dest != NULL);
	assert(src != NULL);
	char* ret = dest;
	while (*dest)
	{
		dest++;
	}
	while (*dest++ = *src++)
	{
		;
	}
	return ret;
}

int main()
{
	char str1[] = "world";
	char str2[20] = "hello ";
	My_strcat(str2, str1);
	printf("%s\n", str2);
	//printf("%s\n", My_strcat(str2, str1));
	return 0;
}